<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<script>
function draw() {
var ctx = document.getElementById('c').getContext('2d');

ctx.beginPath();
ctx.arc(75, 75, 74, 0, 2 * Math.PI);
ctx.closePath();
ctx.fill();

ctx.globalCompositeOperation = 'destination-out';
ctx.shadowColor = 'rgba(0, 0, 0, 0.8)';
ctx.shadowBlur = 3;
ctx.beginPath();
ctx.arc(75, 75, 40, 0, 2 * Math.PI);
ctx.closePath();
ctx.fill();
ctx.shadowBlur = 0;

ctx.globalCompositeOperation = 'source-over';
ctx.lineWidth = 10;
ctx.strokeStyle = 'green';
ctx.beginPath();
ctx.arc(75, 75, 40, 0, 2 * Math.PI);
ctx.closePath();
ctx.stroke();
}
</script>
</head>
<body onload='draw()' style='background: white;'>
<canvas id='c' width='200' height='200'></canvas>
</body>
</html>
